<!DOCTYPE html>
<html lang="zh-Hans">

<head>
    <meta charset="utf-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge, chrome=1" />
    <meta name="viewport"
        content="width=device-width, initial-scale=1.0,maximum-scale=1,minimum-scale=1,user-scalable=no">

    <link rel="stylesheet" href="./css/selector_class.css" />
</head>

<body>

    <span class="color">我是一个span标签, class="color"</span>

    <p class="color">我是一个p标签, class="color"</p>

    <p>我是一个div，class="box_red"</p>
    <div class="box_red">
    </div>
    <p>我是一个div，class="box_blue"</p>
    <div class="box_blue">
    </div>
    <p>我是一个div，class="box_red box_blue"</p>
    <div class="box_red box_blue">
    </div>
</body>

</html>